Recovery from olfactory and gustatory dysfunction following COVID-19 acquired during Omicron BA.1 wave in Italy.

BACKGROUND: Despite alterations in the sense of smell and taste have dominated the symptoms of SARS-CoV-2 infection, the prevalence and the severity of self-reporting COVID-19 associated olfactory and gustatory dysfunction has dropped significantly with the advent of the Omicron BA.1 subvariant. However, data on the evolution of Omicron-related chemosensory impairment are still lacking. OBJECTIVE: The aim of the present study was to estimate the prevalence and the recovery rate of self-reported chemosensory dysfunction 6-month after SARS-CoV-2 infection acquired during the predominance of the Omicron BA.1 subvariant in Italy. METHODS: Prospective observational study based on the sino-nasal outcome tool 22 (SNOT-22), item "sense of smell or taste" and additional outcomes conducted in University hospitals and tertiary referral centers in Italy. RESULTS: Of 338 patients with mild-to-moderate COVID-19 completing the baseline survey, 294 (87.0 %) responded to the 6-month follow-up interview. Among them, 101 (34.4 %) and 4 (1.4 %) reported an altered sense of smell or taste at baseline and at 6 months, respectively. Among the 101 patients with COVID-19-associated smell or taste dysfunction during the acute phase of the disease, 97 (96.0 %) reported complete resolution at 6 months. The duration of smell or taste impairment was significantly shorter in vaccinated patients (p = 0.007). CONCLUSIONS: Compared with that observed in subjects infected during the first wave of the pandemic, the recovery rate from chemosensory dysfunctions reported in the present series of patients infected during the predominance of the Omicron BA.1 subvariant was more favorable with a shorter duration being positively influenced by vaccination.

COVID-19 and deafness: Impact of face masks on speech perception

Background: The COVID-19 pandemic has made wearing face masks a common habit in public places. Several reports have underlined the increased difficulties encountered by deaf people in speech comprehension, resulting in a higher risk of social isolation and psychological distress. Purpose: To address the detrimental effect of different types of face masks on speech perception, according to the listener hearing level and background noise. Research design: Quasi-experimental cross-sectional study. Study sample: Thirty patients were assessed: 16 with normal hearing [NH], and 14 hearing-impaired [HI] with moderate hearing loss. Data collection and analysis: A speech perception test (TAUV) was administered by an operator trained to speak at 65 dB, without a face mask, with a surgical mask, and with a KN95/FFP2 face mask, in a quiet and in a noisy environment (cocktail party noise, 55 dB). The Hearing Handicap Index for Adults (HHI-A) was administered twice, asking subjects to complete it for the period before and after the pandemic outburst. A 2-way repeated-measure analysis of variance was performed. Results: The NH group showed a significant difference between the no-mask and the KN95/FFP2-mask condition in noise (p = 0.01). The HI group showed significant differences for surgical or KN95/FFP2 mask compared with no-mask, and for KN95/FFP2 compared with surgical mask, in quiet and in noise (p < 0.001). An increase in HHI-A scores was recorded for the HI patients (p < 0.001). Conclusion: Face masks have a detrimental effect on speech perception especially for HI patients, potentially worsening their hearing-related quality of life. (PsycInfo Database Record (c) 2023 APA, all rights reserved)

Exploratory Study on Chemosensory Event-Related Potentials in Long COVID-19 and Mild Cognitive Impairment: A Common Pathway?

People affected by the Long COVID-19 (LC) syndrome often show clinical manifestations that are similar to those observed in patients with mild cognitive impairments (MCI), such as olfactory dysfunction (OD), brain fog, and cognitive and attentional diseases. This study aimed to investigate the chemosensory-evoked related potentials (CSERP) in LC and MCI to understand if there is a common pathway for the similarity of symptoms associated with these disorders. Eighteen LC patients (mean age 53; s.d. = 7), 12 patients diagnosed with MCI (mean age 67; s.d. = 6), and 10 healthy control subjects (mean age 66; s.d. = 5, 7) were recruited for this exploratory study. All of them performed a chemosensory event-related potentials (CSERP) task with the administration of trigeminal stimulations (e.g., the odorants cinnamaldehyde and eucalyptus). Study results highlighted that MCI and LC showed reduced N1 amplitude, particularly in the left frontoparietal network, involved in working memory and attentional deficits, and a reduction of P3 latency in LC. This study lays the foundations for evaluating aspects of LC as a process that could trigger long-term functional alterations, and CSERPs could be considered valid biomarkers for assessing the progress of OD and an indicator of other impairments (e.g., attentional and cognitive impairments), as they occur in MCI.

Comparison of prevalence and evolution of COVID-19 olfactory disorders in patients infected by D614 (wild) and B.1.1.7. Alpha variant: a brief report.

OBJECTIVES: To investigate the prevalence and the evolution of olfactory disorders (OD) related to coronavirus disease 2019 (COVID-19) in patients infected during the first and the second European waves. METHODS: From March 2020 to October 2020, COVID-19 patients with OD were recruited and followed over the 12-month post-infection. The following data were collected: demographic, treatments, vaccination status, and olfactory function. Olfaction was assessed with the Olfactory Disorder Questionnaire (ODQ), and threshold, discrimination, and identification (TDI) test. Outcomes were compared between patients of the first wave (group 1: wild/D614G virus) and the second wave (group 2: B.1.1.7. Alpha variant) at 1-, 3- and 12-month post-infection. RESULTS: Sixty patients completed the evaluations accounting for 33 and 27 patients in group 1 and 2, respectively. The 1-month TDI score (23.7 ± 5.3) was significantly lower in group 2 compared to group 1 (29.8 ± 8.7; p = 0.017). Proportion of normosmic patients at 1-month post-infection was significantly higher in group 1 compared to group 2 (p = 0.009). TDI scores only significantly increased from 1- to 3-month post-infection in anosmic and hyposmic patients. Focusing on There was a negative association between the 1-month ODQ and the 1-month TDI (rs = - 0.493; p = 0.012). ODQ was a significant predictor of TDI scores at 3- and 12-month post-infection. The 12-month prevalence of parosmia was 60.6% in group 1 and 42.4% in group 2, respectively. There was no significant influence of oral corticosteroid treatment, adherence to an olfactory training and vaccination status on the olfactory outcomes. CONCLUSIONS: Patients of the second wave (Alpha B.1.1.7. variant) reported significant higher proportion of psychophysical test abnormalities at 1-month post-infection than patients infected during the first wave (D614G virus).

SARS-CoV-2 Effects on Psychophysical Olfactory Scores: Prospective Study With Evaluation Before and 60-Days After Infection.

The aim of this study was to prospectively evaluate the olfactory function in a series of individuals infected with SARS-CoV-2 and who had undergone psychophysical olfactory assessment prior to infection. Individuals unexposed to SARS-CoV-2 infection underwent a psychophysical evaluation of smell with the Sniffin' Sticks test. The subjects were followed prospectively and included in the study if they developed SARS-CoV-2 infection with a second test 60 days after recovery. At the 60-day follow-up of the 41 included subjects, 2 (4.9%) self-reported persistent olfactory dysfunction (OD). The differences between TDI scores before and after infection were statistically significant (37 [interquartile range (IQR), 34.25-39.25] vs 34.75 [IQR, 32.25-38]; p = .021). Analyzing the individual olfactory domains, the differences were significant for threshold (T) (9.75 [IQR, 9-11.25] vs 8.25 [IQR, 7.25-10.25]; p = .009) but not for odor discrimination (D) (p = .443) and identification (I) (p = .159). SARS-CoV-2 causes a significant reduction in the olfactory function, in particular affecting the olfactory threshold, even in subjects who do not self-report an OD.

Parosmia as a predictor of a better olfactory function in COVID-19: a multicentric longitudinal study for upper respiratory tract infections.

PURPOSE: This study aimed to evaluate the course of olfactory dysfunction [OD] due to upper respiratory tract infections [URTI] especially for COVID-19 [C19] in a multicentric design and to investigate possible predictors for the outcome. METHODS: In a multicentric study, patients (n = 147, of which 96 were women) with OD due to URTI, including C19 and non-C19 were evaluated at two visits with a standardized medical history and "Sniffin' Sticks" extended psychophysical testing to examine the course and possible predictors for improvement of olfactory function. RESULTS: C19 patients showed better overall olfactory function (p < 0.001) compared to non-C19. Olfactory function (p < 0.001) improved over 3.5 ± 1.2 months in a comparable fashion for C19 and non-C19 comparable over time (p = 0.20) except for a more pronounced improvement of odour threshold (p = 0.03) in C19. C19 patients with parosmia exhibited a higher probability of clinically relevant improvement of odour threshold, a better threshold in the second visit, and tended to have a better TDI-score at the second visit. Further possible predictors for an improving olfactory function were younger age, female gender, and had lower scores in olfactory tests at the first visit. CONCLUSIONS: Patients with C19 and non-C19 URTI exhibit a similar improvement over 3-4 months except for the odour threshold, with a better TDI in both visits for C19. For C19 a better prognosis in terms of olfactory recovery was found for younger patients with parosmia and lower olfactory scores at the first visit. Still, for many patients with olfactory loss, an improvement that is experienced as complete may only occur over months and possibly years.

Psychophysical assessment of olfactory and gustatory function in post-mild COVID-19 patients: A matched case-control study with 2-year follow-up.

BACKGROUND: The aim of this study was to psychophysically evaluate the prevalence of smell and taste dysfunction 2 years after mildly symptomatic severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection compared to that observed at 1-year follow-up and while considering the background of chemosensory dysfunction in the no-coronavirus disease 2019 (COVID-19) population. METHOD: This is a prospective case-control study on 93 patients with polymerase chain reaction (PCR)-positive SARS-CoV-2 infection and 93 matched controls. Self-reported olfactory and gustatory dysfunction was assessed by 22-item Sino-Nasal-Outcome Test (SNOT-22), item "Sense of smell or taste." Psychophysical orthonasal and retronasal olfactory function and gustatory performance were estimated using the extended Sniffin' Sticks test battery, 20 powdered tasteless aromas, and taste strips test, respectively. Nasal trigeminal sensitivity was assessed by sniffing a 70% solution of acetic acid. RESULTS: The two psychophysical assessments of chemosensory function took place after a median of 409 days (range, 366-461 days) and 765 days (range, 739-800 days) from the first SARS-CoV-2-positive swab, respectively. At 2-year follow-up, cases exhibited a decrease in the prevalence of olfactory (27.9% vs. 42.0%; absolute difference, -14.0%; 95% confidence interval [CI], -21.8% to -2.6%; p = 0.016) and gustatory dysfunction (14.0% vs. 25.8%; absolute difference, -11.8%; 95% CI, -24.2% to 0.6%; p = 0.098). Subjects with prior COVID-19 were more likely than controls to have an olfactory dysfunction (27.9% vs. 10.8 %; absolute difference, 17.2%; 95% CI, 5.2% to 28.8%) but not gustatory dysfunction (14.0% vs. 9.7%; absolute difference, 4.3%; 95% CI, -5.8% to 14.4% p = 0.496) still 2 years after the infection. Overall, 3.2% of cases were still anosmic 2 years after the infection. CONCLUSIONS: Although a proportion of subjects recovered from long-lasting smell/taste dysfunction more than 1 year after COVID-19, cases still exhibited a significant excess of olfactory dysfunction 2 years after SARS-CoV-2 infection when compared to matched controls.

COVID-19-Related Quantitative and Qualitative Olfactory and Gustatory Dysfunction: Long-Term Prevalence and Recovery Rate.

INTRODUCTION: No studies have reported data on 2-year prevalence and recovery rates of self-reported COVID-19-related quantitative and qualitative olfactory and gustatory dysfunction. The aim of the present study was to estimate the 2-year prevalence and recovery rate of self-reported COVID-19-related olfactory and gustatory dysfunction in a cohort of patients with antecedent mild-to-moderate disease. METHODS: This is a prospective observational study, measuring the prevalence of altered sense of smell or taste at follow-up and their variation from baseline, on adult patients consecutively assessed at Trieste University Hospital, who tested positive for SARS-CoV-2 RNA by polymerase chain reaction during March 2020. RESULTS: Overall, 174 (68.8%), 53 (20.9%), and 36 (14.2%) of 253 responders reported an altered sense of smell or taste (SNOT-22 >0) at baseline, 12 months, and 24 months, respectively. Among the 174 patients who have complained a COVID-19-associated olfactory or gustatory dysfunction at baseline, 138 (79.3%) reported complete resolution of smell or taste impairment with 17 subjects (9.8%) recovering after more than 1 year after the initial infection, 33 (19.0%) reported a decrease in the severity, and only 3 (1.7%) reported that the symptom was unchanged at the 24-month interview. Twenty subjects (7.9%) complained of at least one qualitative long-term symptom. CONCLUSION: Two years after the infection, most patients experience a favourable evolution of COVID-19-related olfactory or gustatory dysfunction. A late recovery was observed in 10% of subjects.

Supporting Cells of the Human Olfactory Epithelium Co-Express the Lipid Scramblase TMEM16F and ACE2 and May Cause Smell Loss by SARS-CoV-2 Spike-Induced Syncytia.

BACKGROUND/AIMS: Quantitative and qualitative alterations in the sense of smell are well established symptoms of COVID-19. Some reports have shown that non-neuronal supporting (also named sustentacular) cells of the human olfactory epithelium co-express ACE2 and TMPRSS2 necessary for SARS-CoV-2 infection. In COVID-19, syncytia were found in many tissues but were not investigated in the olfactory epithelium. Some studies have shown that syncytia in some tissues are formed when SARS-CoV-2 Spike expressed at the surface of an infected cell binds to ACE2 on another cell, followed by activation of the scramblase TMEM16F (also named ANO6) which exposes phosphatidylserine to the external side of the membrane. Furthermore, niclosamide, an approved antihelminthic drug, inhibits Spike-induced syncytia by blocking TMEM16F activity. The aim of this study was to investigate if proteins involved in Spike-induced syncytia formation, i.e., ACE2 and TMEM16F, are expressed in the human olfactory epithelium. METHODS: We analysed a publicly available single-cell RNA-seq dataset from human nasal epithelium and performed immunohistochemistry in human nasal tissues from biopsies. RESULTS: We found that ACE2 and TMEM16F are co-expressed both at RNA and protein levels in non-neuronal supporting cells of the human olfactory epithelium. CONCLUSION: Our results provide the first evidence that TMEM16F is expressed in human olfactory supporting cells and indicate that syncytia formation, that could be blocked by niclosamide, is one of the pathogenic mechanisms worth investigating in COVID-19 smell loss.

ENT symptoms in acute COVID-19: a narrative review Sintomi ORL durante la fase acuta della COVID-19: una revisione narrativa

SUMMARY Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is characterised by a wide spectrum of disease severity ranging from asymptomatic or oligosymptomatic cases to severe and life-threatening forms. As this new coronavirus is a respiratory virus, it is not surprising that many symptoms caused by SARS-CoV-2 infection are related to the involvement of the upper respiratory tract. In addition the most pathognomonic of symptoms, i.e. the alteration of smell, nasal obstruction, sore throat and cough have been consistently described as early symptoms of the disease. However, for other ENT symptoms, such as oral lesions and audio-vestibular changes, a causal relation is far from proven. The rapid and extensive spread of COVID-19 makes it difficult to demonstrate a causative link between several ENT symptoms and SARS-CoV-2 infection and it is reasonable to assume that at least in some cases this link is actually coincidental in some cases. Moreover, following the phenomenon of the race to publish, there has been an uncontrolled release of poor-quality articles showing the most disparate associations mainly based on a temporal association between SARS-CoV-2 infection and symptoms of various types including those of the ENT area. In this narrative review of the literature, we will critically describe the ENT symptoms of COVID-19.